1. Field of the Invention
The invention relates to a method for regulating the pressure in an electronically controlled brake system, and an electronic brake system.
2. Description of the Related Art
In the course of the last decades, the motorcycle has developed from a low-cost means of transport to a leisure vehicle in which both safety and rider comfort have moved into the foreground.
Similarly to cars a few years ago, motorcycles are increasingly being equipped with antilock brake systems (ABS). For example, an antilock device for motorcycles is known from EP 0 548 985 61. Furthermore, a method for antilock braking of a motorcycle and for determining the coefficient of adhesion is known from DE 40 00 212 A1.
Traditionally, motorcycles have had an actuating element for each of the two brake circuits. Usually, the front wheel brake is actuated by a “hand brake lever” and the rear wheel brake by a “foot brake lever”.
In relation to motorcycles, an “integral brake system” is understood to mean a brake system in which, upon actuation of the hand brake lever or the foot brake lever, the brake of the second brake circuit is additionally braked by an active pressure increase. Both brakes can therefore be operated by actuation of a single actuating element. If both brakes are operated by actuation of both the hand brake lever and the foot brake lever, this is referred to as a fully integral brake. However, combinations in which one brake lever acts on one wheel and the other brake lever on both wheels (partially integral brake) are also possible. Integral brake systems for motorcycles are known, for example, from DE 38 03 563 A1 and DE 103 16 351 A1.
In motorcycles with integral function, as a result of actuation of a single actuating element (e.g. hand brake lever and/or foot brake lever), automatic brake force distribution or brake pressure distribution between front wheel and rear wheel takes place either through fixed hydraulic circuitry, by means of which the brake force distribution is predefined invariably at a given ratio, or through an electronic system by means of which the predetermined brake force distribution is controlled. With electronic systems with integral brake function and antilock function, the brake force distribution between front and rear wheel with ABS braking can be adapted to the actual load (Bremsenhandbuch, 2nd edition July 2004, Vieweg Verlag, ISBN 3-528-13952-8, pages 184-192).
A brake system for motorcycles which ensures the functionality of ABS and integral braking in combination with a constructionally simple structure is known from DE 10 2005 003 255 A1.
Because of the increased safety and/or enhanced comfort, It can be expected that partially or fully integral brake systems on motorcycles, which assist the rider by active pressure increase at the front and/or rear wheel during the braking process and therefore ensure an optimized braking distance, will be increasingly used in future.
In order to hold a motorcycle on an uphill gradient, it has been necessary up to now for the rider to prevent the vehicle from rolling back by operating the front wheel and/or rear wheel brake. In the case of motorcycles without an integral brake system, actuation of the hand brake lever (front wheel brake) alone can in some cases be insufficient to hold the vehicle securely on steep uphill gradients. The rider must then also operate the foot brake lever in order to hold the vehicle.
On motorcycles with an integral brake system and on motorcycles without an integral brake system, holding the vehicle by operating the hand brake lever and then starting becomes a relatively complex sequence of movements requiring fine motor control, since both the hand brake lever and the throttle control must be operated with the right hand. This represents a challenge even for an experienced rider.
Operation of the foot brake lever for holding the motorcycle poses major challenges especially for shorter riders, since only one leg is now available for stabilizing the motorcycle.
It is therefore an object of the invention to make available a method for regulating the brake pressure in an electronically controlled brake system of a motorcycle, in particular an integral brake system for a motorcycle, and an electronic brake system for a motorcycle, in particular an integral brake system for a motorcycle, which simplifies holding the motorcycle and/or starting.